Vehicular fuel senders have been known for many decades as fuel tank mounted devices that provide a representation usually in the form of an electric signal of the quantity of fuel remaining in the tank. These representations or signals are utilized to drive fuel indicating devices commonly found in th operating compartment of the vehicle. In the past these fuel senders have commonly taken the form of a float-driven rheostat cantilevered into the tank through an opening in one of the tank walls. These fuel sender assemblies also include a rheostat supporting frame welded or soldered to a top plate covering the tank access opening along with fuel inlet and outlet tubes that are soldered to and pass through the top plate. They are quite light in weight and require no more support than a simple clamping ring that holds the supporting top plate over the access opening.
Over the last decade fuel injection systems have been increasingly popular, particularly systems in which the number of injectors is less than the number of piston and cylinder devices in the associated internal combustion engine. With the advent of these fuel injection systems it has become desirable to mount the pump directly in the fuel tank rather than in the engine compartment itself, the previously common location for fuel pumps in internal combusiton engine driven vehicles. The logical cost-effective location for these submersible pumps is on the cantilevered fuel sender assembly.
While the submersible fuel pumps are quite small, they are relatively heavy and cause vibration as they rotate imposing unusually high loadings at the junctures between the inlet and outlet tubes and the sender frame and the top plate that in some cases cause failure in one or more of these joints.
To obviate this problem it has been suggested that the combined fuel pump and fuel sender assembly be provided with a spring that reacts against the side of the fuel tank opposite the access opening mounting. One such device of this type includes a generally U-shaped leaf spring connected to the lower part of the assembly, with spring ends that engage and bias against the opposite wall of the fuel tank.
While such spring arrangements reduce pump vibration to some extent, the vibration is directional and acts mainly perpendicular to the axis of rotation of the fuel pump and the springs do not provide significant vibration limiting or absorption in this direction. Because the fuel pump is most conveniently mounted with its axis parallel to the axis of the supporting frame, the fuel pump's vibrational motion in a plane transverse to its axis even with such springs continues to result in excessive strain being imposed upon the joints at the assembly top plate.
Another problem in submersible pump assemblies is the transmission of noise from the fuel pump to the fuel tank.
It is the primary object of the present invention to ameliorate the problems noted above in supporting a fuel pump-fuel sender assembly within a fuel tank.